{
    let aaa = "abc";
    let bbb = 88;
    let ccc = [aaa,bbb];
    // 如果ccc是一个数组，ddd就是字符串或数字
    let ddd = ccc[1];
    ddd = "bcd";
    ddd = 99;
    console.log(ddd);

    let eee = [aaa,bbb] as const;
    // eee是一个元组，fff就是一个数字
    let fff = eee[1];
    fff = 0;
    // fff = "opq";
    console.log(fff);
}